This invention relates to a new and distinct cultivar of the Saxifragaceae family. The botanical name of the plant is Hydrangea macrophylla (Thunb.). The varietal denomination is `Frau Katsuko`. The new cultivar originated as a seedling from the inventor's controlled crossing as pollen and seed parents, respectively, the varieties known as, `Madam Blumkock` and `Silver-Edge` in Tochigi-Prefecture, Japan. `Frau Katsuko` was discovered and selected as one flowering plant within the progeny of the stated parentage in a controlled environment. `Frau Katsuko` is distinguished from its parents, and all other varieties of Hydrangea macrophylla of which I am aware, by the combination of the attractive pigmentation pattern of its sepals which is predominently colored with deep, irregular, white edges; its deeply serrated, ruffled edges; and its dense inflorescence on a strong stem that does not require staking for support. This new cultivar has been successfully asexually reproduced under controlled environmental conditions at a nursery in Half Moon Bay, Calif. under the direction of the inventor over a three year period with its distinguishing characteristics remaining stable.
Sepal color of `Frau Katsuko` is predominately blue or red with a deep irregular, white edge pattern, The pigmentation is darkest at the apex and fades slightly as it progresses across the length and width of the sepals, and then turns white as far as 5 mm from edge. Color pigmentation often reaches the edge of the sepal, but only at the apex. Sepal pigmentation of individual Hydrangea macrophylla plants depends on the nutrients and pH of the growing medium. The sepal coloration of the pollen parent `Madam Blumkock`,is uniformly pink. The sepals of seed parent, `Silver-Edge`, has a uniform red pigmentation with white edges. The new variety of Hydrangea as described herein is further characterized by its compact growth habit, the ease with which it can be forced in a greenhouse, and its large, long lasting flowers that do not need to be staked. Mature flowers slowly fade to green and ultimately brown with age.
Asexual reproduction was first accomplished when vegetative cuttings were taken by the inventor from the initially selected plant. Examination of asexually reproduced, successive generations grown in a controlled environment at Half Moon Bay, Calif. show that the combination of characteristics as herein disclosed for `Frau Katsuko` is firmly fixed. Asexual reproduction of successive generations at Half Moon Bay was achieved by taking vegetative cuttings from selected plants over three years. Each new generation over the three years retained the combination of characteristics as herein disclosed for `Frau Katsuko`.